Ah, the issue is with the ssh urls including the : to delimit the host from the path. Since ssh is the git default transport if it has an "scp-like" url, just stripping off the ssh:// is probably best.

"For public repos you own or are a collaborator on, and all private repos, you must use a private ssh url like git@github.com:user/repo.git. You can find each of the URLs available to you in the header of the repo page:"